The names of sushi usually come from the "neta" (ingredients placed on top of the sushi, such as fish, shrimp, shellfish, or squid). However, the rolled sushi (makizushi) served in the latter half of omakase often has unique names unrelated to the ingredients.

For example, rolled sushi made with tuna (maguro) red flesh (akami) and wasabi is called tekkamaki. But why is it called tekkamaki (鉄火巻き) instead of maguro maki (マグロ巻き)? There are a few theories about this.

The first theory is that "tekka" (鉄火) originally referred to the state of iron turning red when heated or the sparks flying when hammered. The name tekkamaki is said to have come from the resemblance between the red color of tuna akami and heated iron.

The second theory links the name tekkamaki to gambling culture. In old Japan, gambling dens were called "tekkaba" (鉄火場). Gamblers favored maguro maki as it could be eaten with one hand without getting their hands dirty during games, which led to the name tekkamaki.

Both theories provide intriguing background to the name tekkamaki.